Bump MSRV to Rust 1.63.0

As being done in the rest of the Rust Bitcoin ecosystem; bump MSRV to
Rust `v1.63.0`.

.github/workflows/rust.yml

@@ -61,7 +61,7 @@ jobs:
         run: ./contrib/test.sh
 
   MSRV:
-    name: Test - 1.56.1 toolchain
+    name: Test - 1.63.0 toolchain
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
@@ -71,7 +71,7 @@ jobs:
       - name: Checkout Toolchain
         uses: dtolnay/rust-toolchain@stable
         with:
-          toolchain: "1.56.1"
+          toolchain: "1.63.0"
       - name: Running test script
         env:
           DO_NO_STD: true

Cargo.toml

@@ -9,7 +9,7 @@ categories = ["cryptography::cryptocurrencies"]
 keywords = [ "psbt", "bip-174", "bip174", "bip-370", "bip370"]
 readme = "README.md"
 edition = "2021"
-rust-version = "1.56.1"
+rust-version = "1.63.0"
 exclude = ["tests", "contrib"]
 
 [package.metadata.docs.rs]
@@ -56,6 +56,3 @@ required-features = ["std"]
 [[example]]
 name = "v2-separate-creator-constructor"
 required-features = ["std"]
-
-[lints.rust]
-unexpected_cfgs = { level = "deny", check-cfg = ['cfg(rust_v_1_60)'] }

README.md

@@ -10,7 +10,7 @@ For now we more or less just follow the contribution guidelines of
 
 ### Minimum Supported Rust Version (MSRV)
 
-This library should always compile with any combination of features on **Rust 1.56.1**.
+This library should always compile with any combination of features on **Rust 1.63.0**.
 
 To build with the MSRV you will likely need to pin a bunch of dependencies, see `./contrib/test.sh`
 for the current list.

clippy.toml

@@ -1 +1 @@
-msrv = "1.56.1"
+msrv = "1.63.0"

src/lib.rs

@@ -74,7 +74,7 @@ mod prelude {
     #[cfg(all(not(feature = "std"), not(test)))]
     pub use alloc::{string::{String, ToString}, vec::Vec, boxed::Box, borrow::{Borrow, BorrowMut, Cow, ToOwned}, slice, rc};
 
-    #[cfg(all(not(feature = "std"), not(test), any(not(rust_v_1_60), target_has_atomic = "ptr")))]
+    #[cfg(all(not(feature = "std"), not(test), target_has_atomic = "ptr"))]
     pub use alloc::sync;
 
     #[cfg(any(feature = "std", test))]